Trehalose synthase protein, gene, plasmids, microorganisms, and a process for producing trehalose

ABSTRACT

The present invention relates to a trehalose-producing microorganism and a process for producing trehalose. It also to a novel trehalose synthase protein, a trehalose synthase gene, recombinant plasmids carrying said trehalose synthase gene, and transformed microorganism with said recombinant plasmids.

This application is the national phase under 35 U.S.C. § 371 of PCT International Application No. PCT/KR99/00131 which has an International filing date of Mar. 24, 1999, which designated the United States of America and was published in English.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a trehalose-producing microorganism and a process for producing trehalose. It also relates to a novel trehalose synthase protein, a trehalose synthase gene, recombinant plasmids carrying said trehalose synthase gene, and transformed microorganisms with said recombinant plasmids.

2. Description of the Prior Art

Trehalose is a non-reducing disaccharide, two saccharides of which are linked by α-1,1 bond: α-D-glucopyranosyl-α-D-glucopyranoside. It has wide application in medicines, foods, and cosmetics. However, its utilization has been greatly restricted because its production to date has been inefficient and expensive.

Japanese Laid-open Patent Nos. Hei5-91890 and Hei6-145186 disclose methods for extracting trehalose from yeasts. There are several methods for isolating trehalose from fermented microorganism cultures, such as Arthrobacter (T. Suzuki, Agric. Biol. Chem., 33(2), 1969), Nocardia (Japanese Laid-open Patent No. Sho 50-154485), Micrococcus (Japanese Laid-open Patent No. Hei6-319578), amino acid-fermenting yeast, Brevibacterium (Japanese Laid-open Patent No. Hei5-211882), and yeast (Yoshikwa, etc., Biosci. Biotech. Biochem., 1994, 58, 1226-12300). Additionally, a method for producing trehalose by using recombinant plants including bacterial genes capable of converting glucose into trehalose is described in M. Scher, Food Processing, April, 95-96, 1993. Japanese Laid-open Patent No. 83-216695 discloses a method for converting maltose into trehalose by using maltose phosphorylase and trehalose phosphorylase. However, these methods are not effective, because their procedures are complicated and their yields are low.

Several enzymatic methods have been published recently. Japanese Laid-open Patent No. Hei7-143876 and EPO 628630 A2 discloses a two-step enzymatic conversion method in which starch is converted into trehalose by maltooligosyl trehalose synthase and maltooligosyl trehalose trehalohydrolase. Japanses Laid-open Patent No. Hei7-170977 and Korean Laid-open Patent No.95-3444 disclose one-step enzymatic conversion methods in which maltose is directly converted into trehalose by trehalose synthase. However, there is still a need to increase the titer of the trehalose synthase enzyme so that production of trehalose from maltose becomes more efficient in yield and cost.

We have invested much effort over the last several years in isolating microorganisms able to convert maltose into trehalose from soil. We have successfully screened a novel strain which highly expresses trehalose and, unexpectedly, generates no byproducts, unlike all known microorganisms. Its morphological and physiological characteristics identify it as a novel Pseudomonas stutzeri strain. This strain has been designated as Pseudomonas stutzeri CJ38.

We isolated a trehalose synthase gene from chromosomes of Pseudomonas stutzeri CJ38 and determined its nucleotide sequence by cloning it into known vector pUC 18 with restriction enzyme Sau3AI. In addition, we isolated a trehalose synthase protein from Pseudomonas stutzeri CJ38 and determined its amino acid sequence using standard methods. It was found that these sequences are apparently different from the sequences of the trehalose synthase gene and all proteins known hitherto. This invention was achieved by constructing recombinant plasmnids carrying the trehalose synthase gene so that the trehalose synthase enzyme encoded in said gene can be expressed in large amounts.

SUMMARY OF THE INVENTION

The present invention provides a novel microorganism, Pseudomonas stutzeri CJ38, that produces trehalose from maltose. This strain was deposited at the Korea Culture Center of Microorganisms, Seoul, Korea, as the accession number KCCM 10150 on Feb. 12, 1999 under the Budapest Treaty. This strain is very valuable as it does not generate byproducts such as glucose when converts maltose into trehalose.

The present invention also provides SEQ ID NO: 2, which is a novel trehalose synthase protein with the following amino acid sequence:

Met  Ser  Ile  Pro  Asp  Asn  Thr  Tyr  Ile  Glu  Trp  Leu  Val  Ser  Gln                     5                        10                       15 Ser  Met  Leu  His  Ala  Ala  Arg  Glu  Arg  Ser  Arg  His  Tyr  Ala  Gly                     20                       25                       30 Gln  Ala  Arg  Leu  Trp  Gln  Arg  Pro  Try  Ala  Gln  Ala  Arg  Pro  Arg                     35                       40                       45 Asp  Ala  Ser  Ala  Ile  Ala  Ser  Val  Trp  Phe  Thr  Ala  Tyr  Pro  Ala                     50                       55                       60 Ala  Ile  Ile  Thr  Pro  Glu  Gly  Gly  Thr  Val  Leu  Glu  Ala  Leu  Gly                     65                       70                       75 Asp  Asp  Arg  Leu  Trp  Ser  Ala  Leu  Ser  Glu  Leu  Gly  Val  Gln  Gly                     80                       85                       90 Ile  His  Asn  Gly  Pro  Met  Lys  Arg  Ser  Gly  Gly  Leu  Arg  Gly  Arg                     95                       100                      105 Glu  Phe  Thr  Pro  Thr  Ile  Asp  Gly  Asn  Phe  Asp  Arg  Ile  Ser  Phe                     110                      115                      120 Asp  Ile  Asp  Pro  Ser  Leu  Gly  Thr  Glu  Glu  Gln  Met  Leu  Gln  Leu                     125                      130                      135 Ser  Arg  Val  Ala  Ala  Ala  His  Asn  Ala  Ile  Val  Ile  Asp  Asp  Ile                     140                      145                      150 Val  Pro  Ala  His  Thr  Gly  Lys  Gly  Ala  Asp  Phe  Arg  Leu  Ala  Glu                     155                      160                      165 Met  Ala  Tyr  Gly  Asp  Tyr  Pro  Gly  Leu  Tyr  His  Met  Val  Glu  Ile                     170                      175                      180 Arg  Glu  Glu  Asp  Trp  Glu  Leu  Leu  Pro  Glu  Val  Pro  Ala  Gly  Arg                     185                      190                      195 Asp  Ser  Val  Asn  Leu  Leu  Pro  Pro  Val  Val  Asp  Arg  Leu  Lys  Glu                     200                      205                      210 Lys  His  Tyr  Ile  Val  Gly  Gln  Leu  Gln  Arg  Val  Ile  Phe  Phe  Glu                     215                      220                      225 Pro  Gly  Ile  Lys  Asp  Thr  Asp  Trp  Ser  Val  Thr  Gly  Glu  Val  Thr                     230                      235                      240 Gly  Val  Asp  Gly  Lys  Val  Arg  Arg  Trp  Val  Tyr  Leu  His  Tyr  Phe                     245                      250                      255 Lys  Glu  Gly  Gln  Pro  Ser  Lue  Asn  Trp  Leu  Asp  Pro  Thr  Phe  Ala                     260                      265                      270 Ala  Gln  Gln  Leu  Ile  Ile  Gly  Asp  Ala  Leu  His  Ala  Ile  Asp  Val                     275                      280                      285 Thr  Gly  Ala  Arg  Val  Leu  Arg  Leu  Asp  Ala  Asn  Gly  Phe  Leu  Gly                     290                      295                      300 Val  Glu  Arg  Arg  Ala  Glu  Gly  Thr  Ala  Trp  Ser  Glu  Gly  His  Pro                     305                      310                      315 Leu  Ser  Val  Thr  Gly  Asn  Gln  Leu  Leu  Ala  Gly  Ala  Ile  Arg  Lys                     320                      325                      330 Ala  Gly  Gly  Phe  Ser  Phe  Gln  Glu  Leu  Asn  Leu  Thr  Ile  Asp  Asp                     335                      340                      345 Ile  Ala  Ala  Met  Ser  His  Gly  Gly  Ala  Asp  Leu  Ser  Tyr  Asp  Phe                     350                      355                      360 Ile  Thr  Arg  Pro  Ala  Tyr  His  His  Ala  Leu  Leu  Thr  Gly  Asp  Thr                     365                      370                      375 Glu  Phe  Leu  Arg  Met  Met  Leu  Arg  Glu  Val  His  Ala  Phe  Gly  Ile                     380                      385                      390 Asp  Pro  Ala  Ser  Leu  Ile  His  Ala  Leu  Gln  Asn  His  Asp  Glu  Leu                     395                      400                      405 Thr  Leu  Glu  Leu  Val  His  Phe  Trp  Thr  Leu  His  Ala  Tyr  Asp  His                     410                      415                      420 Tyr  His  Tyr  Lys  Gly  Gln  Thr  Leu  Pro  Gly  Gly  His  Leu  Arg  Glu                     425                      430                      435 His  Ile  Arg  Glu  Glu  Met  Tyr  Glu  Arg  Leu  Thr  Gly  Glu  His  Ala                     440                      445                      450 Pro  Tyr  Asn  Leu  Lys  Phe  Val  Thr  Asn  Gly  Val  Ser  Cys  Thr  Thr                     455                      460                      465 Ala  Ser  Val  Ile  Ala  Ala  Ala  Leu  Asn  Ile  Arg  Asp  Leu  Asp  Ala                     470                      475                      480 Ile  Gly  Pro  Ala  Glu  Val  Glu  Gln  Ile  Gln  Arg  Leu  His  Ile  Leu                     485                      490                      495 Leu  Val  Met  Phe  Asn  Ala  Met  Gln  Pro  Gly  Val  Phe  Ala  Leu  Ser                     500                      505                      510 Gly  Trp  Asp  Leu  Val  Gly  Ala  Leu  Pro  Leu  Ala  Pro  Glu  Gln  Val                     515                      520                      525 Glu  His  Leu  Met  Gly  Asp  Gly  Asp  Thr  Arg  Trp  Ile  Asn  Arg  Gly                     530                      535                      540 Gly  Tyr  Asp  Leu  Ala  Asp  Leu  Ala  Pro  Glu  Ala  Ser  Val  Ser  Ala                     545                      550                      555 Glu  Gly  Leu  Pro  Lys  Ala  Arg  Ser  Leu  Tyr  Gly  Ser  Leu  Ala  Glu                     560                      565                      570 Gln  Leu  Gln  Arg  Pro  Gly  Ser  Phe  Ala  Cys  Gln  Leu  Lys  Arg  Ile                     575                      580                      585 Leu  Ser  Val  Arg  Gln  Ala  Tyr  Asp  Ile  Ala  Ala  Ser  Lys  Gln  Ile                     590                      595                      600 Leu  Ile  Pro  Asp  Val  Gln  Ala  Pro  Gly  Leu  Leu  Val  Met  Val  His                     605                      610                      615 Glu  Leu  Pro  Ala  Gly  Lys  Gly  Val  Gln  Leu  Thr  Ala  Leu  Asn  Phe                     620                      625                      630 Ser  Ala  Glu  Pro  Val  Ser  Glu  Thr  Ile  Cys  Leu  Pro  Gly  Val  Ala                     635                      640                      645 Pro  Gly  Pro  Val  Val  Asp  Ile  Ile  His  Glu  Ser  Val  Glu  Gly  Asp                     650                      655                      660 Leu  Thr  Asp  Asn  Cys  Glu  Leu  Gln  Ile  Asn  Leu  Asp  Pro  Tyr  Glu                     665                      670                      675 Gly  Leu  Ala  Leu  Arg  Val  Val  Ser  Ala  Ala  Pro  Pro  Val  Ile.                     680                      685

In addition, the present invention provides SEQ ID NO: 1, which is a novel trehalose synthase gene with the following nucleotide sequence:

GATCGCTGGC GTACTGCAGG TAGAGCAGGC GCATCGGCCC CCAGGGCGCA TCGGCCGGCT 60 CCGCTGTGCC CTGCTGGTTC ATGAAGCGGA CGAAGCGGCC ATCGCGGAAC CGTGGACGCC 120 ATTCGGGGCT GTCCGGGTCG CGGCTGTCGG TGAGCGTGCG CCACAGGTCG CTGCGAAACG 180 GCGGACCGCT CCAAAGCGCG CCGTGGATGG GATCGCCGAG CAGTTCGTGC AGCTCCCAGG 240 AACGTTGCGA ATGCAGCGCG CCGAGGCTCA GGCCATGCAG ATACAGGCGC GGTCGGCGTT 300 CGGCCGGCAG TTCGGTCCAG TAGCCATAGA TCTCGGCGAA TAGCGCGCGG GCCACGTCGC 360 GGCCGTAGTC GGCCTCCACC AGCAGCGCCA GCGGGCTGTT CAGATAGGAG TACTGCAACG 420 CCACGCTGGC GATATCGCCG TGGTGCAGGT ATTCCACTGC GTTCATCGCC GCCGGGTCGA 480 TCCAGCCGGT ACCGGTGGGC GTCACCAGCA CCAGCACCGA TCGCTCGAAG GCGCCGCTGC 540 GCTGCAGCTC GCGCAAGGCC AGACGCGCCC GCTGGCGCGG GGTCTCTGCC GCGCGCAGAC 600 CGACGTAGAC GCGAATCGGC TCGAGCGCCG AGCGGCCGCT CAAGACGCTG ATATCCGCCG 660 CCGACGGGCC GGAGCCGATG AACTCGCGGC CGGTGCGGCC CAGCTCCTCC CAGCGCAGCA 720 ACGAGGCCCG GCTGCCGCTT TTCAGCGGCG AGGCCGGTGG CGCCGTCTCC GGTTCGATCA 780 GGGCGTCGTA CTGCGCGAAG GATGCGTCCA GCATGCGCAG TGCCCGCGCC GCCAGCACAT 840 CGCTGAGCAG CGACCAGAAC AGCGCCAGCG CCACCAGCAC GCCGATCACG TTGGCCAGGC 900 GCCGTGGCAG CACGCGGTCG GCGTGCCGCG AGACGAAGCG CGACACCAGC CGATACAGAC 960 GCGCCAGCGT CAGCAGGATG AGAAAGGTCG CCAGCGCGGT GAGAATGACT TCGAGCAGGT 1020 GCGCACTGCT CACCGGCGGC ATGCCCATCA GCGCGCGTAC CGCGTTCTGC CAGCCGGCGA 1080 CCTGGCTGAG GAAATACCCG GCCAGCAGCA GGCAGCCGAC CGCGATCAGC AGATTGACCC 1140 GCTCGCGCTG CCAGCCTGGG CGCTCCGGCA GTTCCAGATA GCGCCACAGC CAGCGCCAGA 1200 ACACGCCGAG GCCATAGCCC ACCGCCAGCG CCGCGCCGGC CAGCACGCCC TGGCTCAGCG 1260 TCGAGCGCGG CAGCAGCGAT GGCGTCAGCG CCGCGCAGAA GAACAGCGTG CCCAGCAGCA 1320 GGCCGAAACC GGACAGCGAG CGCCAGATAT AGAGGACGGG CAGGTGCAGC ATGAAGATCT 1380 CCGCGGTCGG GTGACGGCGT CGCGCCTCGG CATATCGAGG CGTGTCCGGT CGTGCGGTTC 1440 CCGTGATGGT CCGCAGCAGG CCAATCCGAT GCAACGATGG CCGAGCGGCC GACTCAAACG 1500 TCTACATTTC CCTAGTGCTG CCGGAACCGA TCGCCG 1536 ATG AGC ATC CCA GAC AAC ACC TAT ATC GAA TGG CTG GTC AGC CAG TCC 1584 Met Ser Ile Pro Asp Asn Thr Tyr Ile Glu Trp Leu Val Ser Gln Ser ATG CTG CAT GCG GCC CGC GAG CGG TCG CGT CAT TAC GCC GGC CAG GCG 1632 Met Leu His Ala Ala Arg Glu Arg Ser Arg His Tyr Ala Gly Gln Ala CGT CTC TGG CAG CGG CCT TAT GCC CAG GCC CGC CCG CGC GAT GCC AGC 1680 Arg Leu Trp Gln Arg Pro Try Ala Gln Ala Arg Pro Arg Asp Ala Ser GCC ATC GCC TCG GTG TGG TTC ACC GCC TAT CCG GCG GCC ATC ATC ACG 1728 Ala Ile Ala Ser Val Trp Phe Thr Ala Tyr Pro Ala Ala Ile Ile Thr CCG GAA GGC GGC ACG GTA CTC GAG GCC CTC GGC GAC GAC CGC CTC TGG 1776 Pro Glu Gly Gly Thr Val Leu Glu Ala Leu Gly Asp Asp Arp Leu Trp AGT GCG CTC TCC GAA CTC GGC GTG CAG GGC ATC CAC AAC GGG CCG ATG 1824 Ser Ala Leu Ser Glu Leu Gly Val Gln Gly Ile His Asn Gly Pro Met AAG CGT TCC GGT GGC CTG CGC GGA CGC GAG TTC ACC CCG ACC ATC GAC 1872 Lys Arg Ser Gly Gly Leu Arg Gly Arg Glu Phe Thr Pro Thr Ile Asp GGC AAC TTC GAC CGC ATC AGC TTC GAT ATC GAC CCG AGC CTG GGG ACC 1920 Gly Asn Phe Asp Arg Ile Ser Phe Asp Ile Asp Pro Ser Leu Gly Thr GAG GAG CAG ATG CTG CAG CTC AGC CGG GTG GCC GCG GCG CAC AAC GCC 1968 Glu Glu Gln Met Leu Gln Leu Ser Arg Val Ala Ala Ala His Asn Ala ATC GTC ATC GAC GAC ATC GTG CCG GCA CAC ACC GGC AAG GGT GCC GAC 2016 Ile Val Ile Asp Asp Ile Val Pro Ala His Thr Gly Lys Gly Ala Asp TTC CGC CTC GCG GAA ATG GCC TAT GGC GAC TAC CCC GGG CTG TAC CAC 2064 Phe Arg Leu Ala Glu Met Ala Tyr Gly Asp Tyr Pro Gly Leu Tyr His ATG GTG GAA ATC CGC GAG GAG GAC TGG GAG CTG CTG CCC GAG GTG CCG 2112 Met Val Glu Ile Arg Glu Glu Asp Trp Glu Leu Leu Pro Glu Val Pro GCC GGG CGT GAT TCG GTC AAC CTG CTG CCG CCG GTG GTC GAC CGG CTC 2160 Ala Gly Arg Asp Ser Val Asn Leu Leu Pro Pro Val Val Asp Arg Leu AAG GAA AAG CAC TAC ATC GTC GGC CAG CTG CAG CGG GTG ATC TTC TTC 2208 Lys Glu Lys His Tyr Ile Val Gly Gln Leu Gln Arg Val Ile Phe Phe GAG CCG GGC ATC AAG GAC ACC GAC TGG AGC GTC ACC GGC GAG GTC ACC 2256 Glu Pro Gly Ile Lys Asp Thr Asp Trp Ser Val Thr Gly Glu Val Thr GGG GTC GAC GGC AAG GTG CGT CGC TGG GTC TAT CTG CAC TAC TTC AAG 2304 Gly Val Asp Gly Lys Val Arg Arg Trp Val Tyr Leu His Tyr Phe Lys GAG GGC CAG CCG TCG CTG AAC TGG CTC GAC CCG ACC TTC GCC GCG CAG 2352 Glu Gly Gln Pro Ser Leu Asn Trp Leu Asp Pro Thr Phe Ala Ala Gln CAG CTG ATC ATC GGC GAT GCG CTG CAC GCC ATC GAC GTC ACC GGC GCC 2400 Gln Leu Ile Ile Gly Asp Ala Leu His Ala Ile Asp Val Thr Gly Ala CGG GTG CTG CGC CTG GAC GCC AAC GGC TTC CTC GGC GTG GAA CGG CGC 2448 Arg Val Leu Arg Leu Asp Ala Asn Gly Phe Leu Gly Val Glu Arg Arg GCC GAG GGC ACG GCC TGG TCG GAG GGC CAC CCG CTG TCC GTC ACC GGC 2496 Ala Glu Gly Thr Ala Trp Ser Glu Gly His Pro Leu Ser Val Thr Gly AAC CAG CTG CTC GCC GGG GCG ATC CGC AAG GCC GGC GGC TTC AGC TTC 2544 Asn Gln Leu Leu Ala Gly Ala Ile Arg Lys Ala Gly Gly Phe Ser Phe CAG GAG CTG AAC CTG ACC ATC GAT GAC ATC GCC GCC ATG TCC CAC GGC 2592 Gln Glu Leu Asn Leu Thr Ile Asp Asp Ile Ala Ala Met Ser His Gly GGG GCC GAT CTG TCC TAC GAC TTC ATC ACC CGC CCG GCC TAT CAC CAT 2640 Gly Ala Asp Leu Ser Tyr Asp Phe Ile Thr Arg Pro Ala Tyr His His GCG TTG CTC ACC GGC GAT ACC GAA TTC CTG CGC ATG ATG CTG CGC GAA 2688 Ala Leu Leu Thr Gly Asp Thr Glu Phe Leu Arg Met Met Leu Arg Glu GTG CAC GCC TTC GGC ATC GAC CCG GCG TCA CTG ATC CAT GCG CTG CAG 2736 Val His Ala Phe Gly Ile Asp Pro Ala Ser Leu Ile His Ala Leu Gln AAC CAT GAC GAG TTC ACC CTG GAG CTG GTG CAC TTC TGG ACG CTG CAC 2784 Asn His Asp Glu Leu Thr Leu Glu Leu Val His Phe Trp Thr Leu His GCC TAC GAC CAT TAC CAC TAC AAG GGC CAG ACC CTG CCC GGC GGC CAC 2832 Ala Tyr Asp His Tyr His Tyr Lys Gly Gln Thr Leu Pro Gly Gly His CTG CGC GAA CAT ATC CGC GAG GAA ATG TAC GAG CGG CTG ACC GGC GAA 2880 Leu Arg Glu His Ile Arg Glu Glu Met Tyr Glu Arg Leu Thr Gly Glu CAC GCG CCG TAC AAC CTC AAG TTC GTC ACC AAC GGG GTG TCC TGC ACC 2928 His Ala Pro Tyr Asn Leu Lys Phe Val Thr Asn Gly Val Ser Cys Thr ACC GCC AGC GTG ATC GCC GCG GCG CTT AAC ATC CGT GAT CTG GAC GCC 2976 Thr Ala Ser Val Ile Ala Ala Ala Leu Asn Ile Arg Asp Leu Asp Ala ATC GGC CCG GCC GAG GTG GAG CAG ATC CAG CGT CTG CAT ATC CTG CTG 3024 Ile Gly Pro Ala Glu Val Glu Gln Ile Gln Arg Leu His Ile Leu Leu GTG ATG TTC AAT GCC ATG CAG CCC GGC GTG TTC GCC CTC TCC GGC TGG 3072 Val Met Phe Asn Ala Met Gln Pro Gly Val Phe Ala Leu Ser Gly Trp GAT CTG GTC GGC GCC CTG CCG CTG GCG CCC GAG CAG GTC GAG CAC CTG 3120 Asp Leu Val Gly Ala Leu Pro Leu Ala Pro Glu Gln Val Glu His Leu ATG GGC GAT GGC GAT ACC CGC TGG ATC AAT CGC GGC GGC TAT GAC CTC 3168 Met Gly Asp Gly Asp Thr Arg Trp Ile Asn Arg Gly Gly Tyr Asp Leu GCC GAT CTG GCG CCG GAG GCG TCG GTC TCC GCC GAA GGC CTG CCC AAG 3216 Ala Asp Leu Ala Pro Glu Ala Ser Val Ser Ala Glu Gly Leu Pro Lys GCC CGC TCG CTG TAC GGC AGC CTG GCC GAG CAG CTG CAG CGG CCA GGC 3264 Ala Arg Ser Leu Tyr Gly Ser Leu Ala Glu Gln Leu Gln Arg Pro Gly TCC TTC GCC TGC CAG CTC AAG CGC ATC CTC AGC GTG CGC CAG GCC TAC 3312 Ser Phe Ala Cys Gln Leu Lys Arg Ile Leu Ser Val Arg Gln Ala Tyr GAC ATC GCT GCC AGC AAG CAG ATC CTG ATT CCG GAT GTG CAG GCG CCG 3360 Asp Ile Ala Ala Ser Lys Gln Ile Leu Ile Pro Asp Val Gln Ala Pro GGA CTC CTG GTG ATG GTC CAC GAG CTG CCT GCC GGC AAG GGC GTG CAG 3408 Gly Leu Leu Val Met Val His Glu Leu Pro Ala Gly Lys Gly Val Gln CTC ACG GCA CTG AAC TTC AGC GCC GAG CCG GTC AGC GAG ACC ATC TGC 3456 Leu Thr Ala Leu Asn Phe Ser Ala Glu Pro Val Ser Glu Thr Ile Cys CTG CCC GGC GTG GCG CCC GGC CCG GTG GTG GAC ATC ATT CAC GAG AGT 3504 Leu Pro Gly Val Ala Pro Gly Pro Val Val Asp Ile Ile His Glu Ser GTG GAG GGC GAC CTC ACC GAC AAC TGC GAG CTG CAG ATC AAC CTC GAC 3552 Val Glu Gly Asp Leu Thr Asp Asn Cys Glu Leu Gln Ile Asn Leu Asp CCG TAC GAG GGG CTT GCC CTG GGT GTG GTG AGC GCC GCG CCG CCG GTG 3600 Pro Tyr Glu Gly Leu Ala Leu Arg Val Val Ser Ala Ala Pro Pro Val ATC TGA GCGC 3610 Ile CCTCTTCGCG CGCCCCGGGT CCGCCGCTAT AGTGCGCAGC GCCTGGGGCG CGCATTGCCC 3670 TCGCCGTCGA GACCAGCCCG TGTCGTTCAC TTCGCTTTTC CGCCTTGCGC TGCTGCCGCT 3730 GGCGCTGCTT GCCGCACCCG TCTGGGCGCA GACCGCCTGC CCGCCCGGCC AGCAGCCGAT 3790 CTGCCTGAGC GGCAGCTGCC TCTGCGTGGC GGCCGCCGCC AGCGATCCAC AGGCGGTCTA 3850 CGACCGCGTC CAGCGTATGG CTACGCTGGC CCTGCAGAAC TGGATCCAGC AGTCGCGCGA 3910 CCGCCTGATG GCCGGCGGCG TCGAGCCGAT ACCGCTGCAC ATCCGCTCGC AGCTCGAGCC 3970 GTATTTCGAT CTTGCCGTGC TGGAGAGTGC GCGGTACCGC GTCGGCGACG AGGTGGTGCT 4030 GACTGCCGGC AACACCCTGC TGCGCAACCC GGACGTCAAT GCCGTGACCC TGATCGACGT 4090 CATCGTCTTC CGCCACGAGG AGGATGCCCG GGACAACGTC GCGCTCTGGG CCCATGAGCT 4150 CAAGCACGTC GAGCAATATC TGGACTGGGG CGTCGCCGAG TTCGCCCGGC GCTATACGCA 4210 GGATTTCCGT GCCGTGGAGC GCCCGGCCTA TGCGCTGGAG CGTGAGGTGG AAGAGGCCCT 4270 GCGCGAGACG CAGACGCGGC GCTGAGOCAG CTGATCGGTG CTGCTGCCCG CACTGGGCTG 4330 AAGCCCACCA ATGACGCCGG CGAAAACGAA AAACCCCGCC GAGGCGGGGT TTCTGACGCG 4390 GGTTGTGCGG TCAGCTCAGA ACGCCGGGAC CACGGCGCCC TTGTACTTTT CCTCGATGAA 4450 CTGGCGTACT TGCTCGCTGT GCAGCGCGGC AGCCAGTTTC TGCATGGCAT CGCTGTCCTT 4510 GTTGTCCGGA CGGGCGACCA GAATGTTCAC GTATGGCGAG TCGCTGCCCT CGATCACCAG 4570 GGCGTCCTGG GTCGGGTTCA GCTTGGCTTC CAGCGCGTAG TTGGTGTTGA TCAGCGCCAG 4630 GTCGACCTGG GTCAGCACGC GCGGCAGAGT CGCGGCTTCC AGTTCGCGGA TCTTGATCTT 4690 CTTCGGGTTC TCGGCGATGT CTTCGGCGTG GCGGTGATGC CGGCGCCGTC CTTCAGACCG 4750 ATC 4753

The present invention also provides a recombinant plasmid containing the trehalose synthase gene with the above nucleotide sequence. In a preferred embodiment, the present invention provides are combinant plasmid pCJ104 in which the 4.7 kb Sau3AI DNA fragment of the trehalose svnthase gene of the present invention is cloned into vector plasinid pUC18. This allow for the efficient and high expression of the trehalose synthase gene. In a more preferred embodiment, the present invention provides a recombinant plasmid pCJ122 in which the 2.5 kb BamHI-BglII DNA fragment of the trehalose synthase gene of the present invention is included in a vector plasmid pUC18. allowing for a higher expression of the trehalose synthase gene.

The present invention provides a transformed E. coli with a recombinant plasmid containing the trehalose synthase gene with the above nucleotide sequence. In a preferred embodiment, the present invention provides a transformed E. coli with a recombinant plasmid pCJ104, allowing for production of high levels of the trehalose synthase protein. In a more preferable embodiment, the present invention provides a transformed E. coli with the recombinant plasmid pCJ122, allowing for production of even higher levels of the trehalose synthase protein.

The present invention provides a process for producing trehalose which comprises reacting the trehalose synthase protein with the above amino acid sequence with maltose solution to obtain trehalose.

The present invention provides a process for producing trehalose which comprises crushing a transformed E. coli with a recombinant plasmid containing the trehalose synthase gene with the above nucleotide sequence and reacting the crushed cells with maltose solution to obtain trehalose. In a preferred embodiment, the present invention provides a process for producing trehalose which comprises crushing a transformed E. coli with plasmid pCJ104, centrifuging the crushed cells and reacting the resulting supernatant with maltose solution to obtain trehalose. In a more preferable embodiment, the present invention provides a process for producing trehalose which comprises crushing a transformed E. coli with plasmid pCJ122, centrifuging the crushed cells and reacting the resulting supernatant with maltose solution to obtain trehalose.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows an analysis of saccharides by thin-layer chromatography to which a reaction solution containing sonicated liquid from Pseudomonas stutzeri CJ38 and maltose solution was subjected. The symbols G, M and T indicate glucose, maltose and trehalose, respectively. In the first lane of the gel shown in FIG. 1 is a control containing glucose, maltose and trehalose.

FIG. 2 shows an analysis of saccharides by gas chromatography to which a reaction solution (A) containing sonicated liquid from Pseudomonasstutzeri CJ38 and maltose solution and a standard trehalose specimen (B) were subjected. The symbol Tre indicate trehalose.

FIG. 3 shows an analysis of saccharides by high performance liquid chromatography to which a standard trehalose specimen (A), and specimens (B) and (C) were subjected. Specimen (B) was obtained just after a solution containing sonicated liquid from Pseudomonas stutzeri CJ38 and maltose solution was reacted completely. Specimen (C) was obtained by adding irehalase to a reaction solution containing sonicated liquid from Pseudomonas stutzeri CJ38 and maltose solution after completion of their reaction. The symbols Tre, Mal and Glu indicate trehalose, maltose and glucose, respectively.

FIG. 4 shows a construction map of a recombinant plasmid pCJ104 including a trehalose synthase gene of the present invention.

FIG. 5 shows a restriction map of a 4.7 kb Sau3AI fragment within a recombinant plasmid pCJ104 of the present invention.

FIG. 6 shows a construction map of recombinant plasmids pCJ121 and pCJ122 of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

A microorganism which produces trehalose from maltose by trehalose synthase was isolated from soil and identified as having the morphological and physiological characteristics of Pseudomonas stutzeri. Pseudomonas stutzeri has not been reported to convert maltose into trehalose. Therefore, the microorganism isolated by us can be recognized as a novel Pseudomonas stutzeri strain and has been designated as Pseudomonas stutzeri CJ38.

We constructed the restriction map of a recombinant plasmid pCJ104 of the present invention using various restriction enzymes. Two trehalose synthase gene sequences are known (Biochim. Biophys. Acta 1996, 1290, 1-3 and Biochim. Bophys. Acta 1997, 1334, 28-32). The comparison of the present and known restriction maps revealed that pCJ104 represents different patterns from those known.

Trehalose synthase proteins from known microorganisms have shown similarities in their N-terminus. However, it was found that the N-terminal sequence of the trehalose synthase protein of the present invention is not identical with those of known trehalose synthase proteins. The results are shown in Table 1 below.

TABLE 1 N-terminal Sequences of Trehalose Synthase Proteins Source of Trehalose Synthase N-terminal Sequence Known Thermus aquaticus M-D-P-L-W-Y-K-D-A-V-I-Y-Q- Microbes ATCC 33923 (SEQ ID NO: 3) Pimelobacter sp. R48 S-T-V-L-G-E-E-P-E-W- F-R-T-A-V- F-Y-E- (SEQ ID NO: 4) Pseudomonas putida G-K-W-P-R-P-A-A-F-I-D- H262 (SEQ ID NO: 5) Transformed E. coli S-I-P-D-N-T-Y-I-E-W-L-V- of the Present Invention (SEQ ID NO: 6)

The nucleotide sequence of 4.7 kb Sau3AI fragment within a recombinant plasmid pCJ104 of the present invention and the amino acid sequence of a trehalose synthase protein expressed therefrom were determined (SEQ ID NO: 1).

In addition, the intact sequence of a trehalose synthase protein of the present invention was compared to those of the trehalose synthase proteins disclosed in Biochim. Biophys. Acta 1996, 1290, 1-3 and Biochim. Biophys. Acta 1997, 1334, 28-32. The comparison revealed that there are no similarities between them.

The enzymatic conversion reaction was carried out using crushed E. coli transformant including recombinant plasmids pCJ104 or pCJ122. As a result, the titer of trehalose synthase enzyme from the crushed cells of the present invention was considerably higher than that from the wild type Pseudomonas stutzeri CJ38.

The properties and availabilities of the plasmids and microorganisms used in and prepared by the present invention are shown in Table 2 below.

TABLE 2 Microbes and Plasmids Properties Availability Pseudo- Wild type strain producing the trehalose KFCC- monas synthase enzyme of the present invention 10985 stutzeri CJ38 E. coli hsdΔ5, Δ(lac pro) [F′, Pro⁺, lacI^(q)ZΔM15] Amersham NM522 E. coli [malP,Q::Tn5 ompBCS1 F⁻ araD139Δ(argF⁻ ATCC ATCC lac) 205U169 rpsL150 relA1 flbB5301 deoC1 35467 ptsF25] pCJ104 pUC18 containing 4.7 kb Sau3AI DNA Constructed fragment (trehalose synthase gene), Ap^(r) pCJ121 pUC18 containing 3.35 kb KpnI DNA Constructed fragment (trehalose synthase gene), Ap^(r) (Control) pCJ122 pUC18 containing 2.5 kb BamHI-BgIII DNA Constructed fragment (trehalose synthase gene), Ap^(r) pCJ123 pUC18 containing 1.2 kb BamHI-EcoRI DNA Constructed fragment (Control) pUC18 Ap^(r), 2.7 kb New and England pUC19 Biolabs

Nutrient medium (0.3% broth, 0.5% peptone, pH 6.8) and LB medium (1% tryptone, 0.5% yeast extract, 1% NaCl, pH 7.0) were used for cultivation of Pseudomonas stutzeri and E. coli, respectively. For the culture of cells transformed by electroporation, SOC medium (2% tryptone, 0.5% yeast extract, 10 mM NaCl, 2.5 mM KCl 10 mM MgCl₂, 10 mM MgSO₄, 20 mM glucose) was used. MacConkey agar medium (4% bacto MacConkey agar base, 2.0% maltose, pH 7.0) was used in cloning the trehalose synthase gene. Ampicillin was added in a concentration of 50 mg/L. Gene Pulser (Bio-Rad) was used in transformation of E. coli by electroporatior. The genetic manipulation used in the present invention was carried out in accordance with procedures described in Molecular Cloning, Laboratory Manual, 2^(nd) ed., Sambrook, J., E. F. Frishc and T. Maniatis and Guide to Molecular Cloning Techniques, Methods in Enzymol. Vol. 152, Berger, S. L., A. R. Kimme.

The enzymatic reaction is conducted at pH 6.0 to 11, preferably pH 7.0 to 10, and at temperatures of 4° C. to 45° C., preferably 20° C. to 40° C. Maltose can be used as a substrate in a concentration of less than 50%. The trehalose synthase enzyme can be used in a pure form or in crushed cells.

The following examples illustrate the present invention. From the foregoing description and the following examples, it is believed that those skilled in the art would be able to carry out the invention completely.

EXAMPLE 1 Screening of Microorganism

A platinum loop of microorganisms, isolated from soil, was inoculated in a 500 ml Erleuneyer flask containing 50 ml of LB culture solution (0.5% of yeast extract, 1.0% of bactotrypton, 0.5% of salt) and cultured at 28° C. for 2 days. The culture was centrifuged at 4° C., 8,000 rpm, for 5 minutes. The cells were collected and washed with physiological saline. The washed cells were suspended in 10 ml of phosphate buffer solution (10 mM, pH 7.0). The cells were crushed by an ultrasonicater and the crushed cells were centrifuged at 4° C., 1.200 rpm. for 20 minutes and the supematant was used as a crude enzymatic solution. The concentration of the protein in the crude enzymatic solution was determined by the Bredford method. 100 μg of protein was mixed with 20 μl of 100 mM maltose and 10 μl of 100 mM phosphate buffer solution (pH 7.0). Distilled water was added to the mixture until the total volume reached 100 μl and the reaction occurred at 30° C. for 20 hours. The saccharides present in the reaction solution were analvzed by TLC, HPLC, and GC.

EXAMPLE 2 Analysis of Trehalose by Thin-layer Chromatography (FIG. 1)

After the reaction was completed, 5 μl of the reaction solution were spotted on Kieselgel 60 TLC (Merck, Germany) and placed in a vessel containing a solvent system of n-butanol-pyridine-water (7:3:1) to develop the specimens. It was sprayed with a solution of 20% sulfuric acid in methyl alcohol and dried at 100° C. for 10 minutes. The saccharides in the specimens were thus specified. Among at least 1,000 soil microorganisms investigated, two were confirmed to have the ability to convert maltose into trehalose. FIG. 1 shows that trehalose did not exist in the specimens prior to the reaction but, after completion of the reaction, saccharides were detected at the site of a standard trehalose specimen.

EXAMPLE 3 Analysis of Trehalose by Gas Chromatography (FIG. 2)

After completion of the reaction, 10 μl of the reaction solution was dried by a reduced pressure dryer. The dried product was dissolved in 20 μl of dimethylformamide and the resulting solution was mixed with the same volume of bis(trimethyl)trifluoracetamide to form trimethylsilane derivatives. One μl of aliquot was used in GC analysis. As shown in FIG. 2, the peak of the reaction solution was observed to occur at the same time as with a standard trehalose specimen.

EXAMPLE 4 Analysis of Trehalose by High Performance Liquid Chromatograpby (FIG. 3)

After the reaction was completed, half of the reaction solution was mixed with the same volume of phenol to remove proteins. The specimen solution thus obtained was used in the HPLC analysis. The peak of the specimen was observed to occur at the same time as with a standard trehalose specimen. The remaining half of the reaction solution was heated to 100° C. for 10 minutes to terminate enzyme activity. It was reacted at 37° C. for 10 minutes with trehalase (Sigma) which specifically acts on α-1,1-trehalose. After completion of the reaction, the solution was mixed with the same volume of phenol solution to remove proteins. The solution obtained thus was subjected to HPLC, and as a result the peak disappeared at the same time as with a standard trehalose.

EXAMPLE 5 Identification of Microorganism Capable of Converting Maltose into Trehalose

The soil microorganism of the present invention was observed by electron microscope and is characterized by rod shaped bacteria with flagellum. It was also characterized as aerobic by an O/F test and by Gram-negative. The physiological characteristics of the microorganism are summarized in Table 1. These characteristics of the present microorganism were compared to those of microorganisms described in Bergy's Manual of Systemic Bacteriology, 1984 and in patent publications, and it was classified as Pseudomonas stutzeri, because it is almost identical to that microorganism, physiologically and morphologically.

TABLE 1 DP3 − OFG + GC + ACE − ESC − PLI − URE − CIT + MAL + TDA − PXB − LAC − MLT + MAN + XYL − RAF − SOR − SUC − INO − ADO − COU − H2S − ONP − RHA − ARA − GLU − ARG − LYS − ORN − OXI − TLA −

EXAMPLE 6 Cloning of Trehalose Synthase Gene (FIG. 4)

(1) Isolation of Chromosomal DNA from Pseudomonas stutzeri

Pseudomonas siutzeri was grown in a nutrient medium and at an early resting stage, cells were recovered by centrifugation. The recovered cells were washed twice with TE solution (10 mM Tris-HCI, pH 8.0, 1 mM EDTA, pH 8.0). The washed cells were suspended in 20 mL of STE buffer (20% sucrose, 10 mM Tris, pH 8.0, I mM EDTA, pH 8.0) and 5 mg/mL of lysozyme and RNase A were added to the suspension. The reaction occurred at 37° C. for 2 hours. After the reaction was completed, SDS was added up to a concentration of 1% and the reaction continued at 37° C. for 30 minutes. This solution was reacted with the same volume of phenol for 4 hours and was subjected to centrifugation. SM NaCl was added to the resulting supernatant until its concentration reached 0.1 M. Using a glass bar, a two-fold volume of anhydrous ethanol was added to obtain chromosomal DNA. The chromosomal DNA was washed with 70% ethanol and dissolved in TE solution for use in the next experiment.

(2) Preparation of Genomic Library

The pure chromosomal DNAs isolated from Pseudomonas stutzeri were partially digested with restriction enzyme Sau3AI at 37° C. for 15 to 30 minutes. The restriction enzyme was inactivated with heat and agarose gel electrophoresis was carried out to obtain 3 to 10 kb DNA fragments. As shown in FIG. 5, plasmid pUC18 was digested with BamHI and was treated with calf intestinal phosphatase. The cleaved DNAs were mixed with 3 to 10 kb DNA fragments previously obtained and ligation with T4 DNA ligase was allowed at 15° C. for 16 hours. The recombinants thus obtained were used for tranformation. The transformation was carried out by electroporation as follows. E. coli NM522 was cultured on LB medium for 14 to 15 hours. The resulting culture. was inoculated on 1L LB so that initial absorbency became 0.07 to 0.1 at 600 nm, and then cultivation was allowed until the absorbency reached 0.8. The cells were centrifuged and suspended in 1L of HEPES [N-(2-hydroxyethyl)piperazine-N-(2-ethanesulfonic acid)] buffer solution. The cells were again centrifuge suspended in 500 ml of cold sterile deionized distilled water. The cells were again centrifuged and suspended in 20 ml of 10% glycerol solution. The cells were again centrifuged and suspended in 2 to 3 ml of 10% glycerol solution so that the cell concentration was adjusted to 2-4×10¹⁰/ml. The cell suspension was rapidly frozen and stored at 70° C. The frozen cells could be used for about one month during which time their transformation frequency did not decrease. 40 μL of frozen cell suspension was thawed in ice and the restored suspension was mixed with the ligated DNA solution. The mixture was put in a gene pulser cuvette with a diameter of 0.2 cm and the capacitance and strength of electric field was fixed at 25 uF and 12.5 kV/cm, respectively. After a single electric pulse was passed at resistance of 200 to 400 Ω, 1 ml of SOC medium was immediately added and cultured at 37° C. for 1 hour. The culture was streaked on LB-ampicillin agar medium and cultivation was allowed for 24 hours to obtain at least fifty thousand colonies. These colonies were together cultured in LB broth for 2 hours. DNA was purely isolated using an alkaline lysis and the genomic library was constructed therefrom.

(3) Cloning of Trehalose Synthase Gene E. coli ATCC35467, which is unable to utilize maltose as a carbon source, was transformed with the genomic library obtained from the above by electroporation. The transformed cells were streaked on a MacConkey-ampicillin agar medium containing 20 g/L of maltose. Once the trehalose synthase gene of Pseudomonas stutzeri is introduced into E. coli, maltose is converted into glucose by the trehalase present in E. coli. As the resulting glucose is metabolized, pH decreases and thereby the color of the colonies on the MacConkey agar medium changes from yellowish to red. This principle was applied to the present cloning system. The transformed E. coli ATCC35467 with the genomic library was cultured on a MacConkey agar medium to obtain red colonies. The isolation of plasmid DNA revealed that it contained about 4.7 kb DNA fragient. The plasmid was designated as pCJ104. To assay enzymes, E. coli ATCC35467/pUC18 (control), E. coli ATCC35467/pCJ104 and wild type Pseudomonas stutzeri CJ38 were cultured. E. coil cells were grown on a LB medium until their early resting stage. Pseudomonas stutzeri CJ38 was grown on a nutrient medium. The cells were separated by centrifugation and crushed. The crushed cells were reacted with 20% maltose as substrate in 20 mM diethanolamine as buffer solution at pH of 8.5 to 9.0 and a temperature of 35° C. 1.0% trichloroacetic acid was added to the reaction solution, which was then subjected to centrifuigation and high performance liquid chromatography to assay the quantities of maltose and trehalose. The results are shown in Table 3 below.

TABLE 3 Enzyme Titration Specific activity of enzyme Culture Titer Microorganisms (U*/mg of protein) (U/ml of culture solution) Pseudomonas stutzeri 0.1 0.023 CJ38 E. coli 0 0 ATCC35467/pUC18 E. coli 0.26 0.175 ATCC35467/pCJ104 *U-μmol trehalose/minutes--

Example 7 Restriction Map Construction of Trehalose Synthase Gene (FIG. 5)

The plasmid pCJ104 was separated using conventional methods and treated with various restriction enzymes to construct a restriction map.

The plasmid pCJ104 was subjected to single, double, and triple-digest procedures using about twenty restriction enzymes, such as AatII, BamHI, BglIII, SmaI, EcoRI, EcoRV, KpnI, NcoI, NdeI, PstI, SacI, SacII, SalI, SphI and XhoI. DNA fragments were analyzed by electrophoresis through agarose gel and compared to construct the restriction map.

EXAMPLE 8 Subcloning of Trehalose Synthase Gene and Enzyme Assay

(1) Subcloning of Trehalose Synthase Gene (FIG. 6)

A subcloning was carried out to determine the sites of the trehalose synthase gene in 4.7 kb plasmid pCJ104. The plasmid pCJ104 was cleaved with KpnI and a 3q35 kb fragment was isolated. This fragment was introduced into vector pUCI 18/KpnI/CIP andE. coli NM522 was transformed with the resulting recombinant. The recombinant plasmid pCJ121 with a directional cloning of 3.35 kb fragment into pUC18/KpnI was constructed. In addition, the plasmid pCJ104 was cleaved with double digestions of BamHI and BglII. The 2.5 kb BamHI-BglII fragment thus obtained was purified and ligated into pUC18/BamHI/CIP, followed by transformation of E. coli NM522 with the recombinant. The recombinant plasmid pCJ122 with directional cloning of 2.5 kb BamHI-BglII fragment into pUC18/BamHI was constructed. Finally, the plasmid pCJ104 was double-digested with BamHI and EcoRI and the resulting 1.2 kb BamHI-EcoRI fragment was purified. This fragment was ligated into vector pUCI18/BamHI/EcoRI and E. coli NM522 was transformed with the recombinant. The recombinant plasmid pCJ123 was constructed.

E. coli ATCC35467was transformed with each of the constructed recombinant plasmids. The transformant were cultured on a MacConkey-ampicilline agar medium containing 2.0% maltose (20 g/L) and the color of the colonies formed therefrom was observed. It was observed that the E. coli ATCC35467 carrying pCJ121 and pCJ122 formed red colonies but that the E. coli ATCC35467 carrying pCJ123 formed yellow colonies since it did not decompose maltose. Therefore, it can be seen that the trehalose synthase gene is located in the larger 2.5 kb BamHI-BglII fragment, rather than in the 1.2 kb BamHI-EcoRI fragment.

(2) Titration of Trehalose Synthase of Transformant Containing Subcloned Plasmid

Transformed E. coli ATCC35467/pCJ121, ATCC35467/pCJ122 and ATCC35467/pCJ123 were cultured on an LB-Ap medium until the early resting stage. The cells were recovered by centrifuigation and washed twice with an appropriate volume of 20 mM diethanolamine solution. The washed cells were suspended in an appropriate volume of 20 mM diethanolamine solution and crushed by ultrasonicater. The crushed cells were centrifuged and the supematant obtained therefrom was used as enzymatic liquid. The supematant was reacted with 20% maltose solution containing 20 mM diethanolamine, pH 8.5 to 9.0 at 35° C. 1.0% trichloroacetic acid was added to the reaction solution, and centrifugation and HPLC were conducted for analysis. One unit of enzyme activity was defined as a quantity of enzyme when it produced 1 μl of trehalose per minute. The results are shown in Table 5 below.

According to the double titration, the enzyme titer of E. coli ATCC35467/pCJ122 was the highest E. coil ATCC35467/pCJ122 was cultured in high density under the conditions described in Table 6 below in 5 L fermenter. As a result, the non-enzymatic activity was 5.0 U/mg of protein, equal to that obtained by culturing it on an LB medium and the titer of the trehalose synthase enzyme in the high density culture was increased to 30 U/ml of culture (Table 5). The non-enzymatic activity and culture titer of E. coli ATCC35467/pCJ122 were increased 50 times and about 1,300 times, respectively, compared to wild type Pseudomonas stutzeri.

TABLE 5 Specific activity of enzyme Culture Titer of 5 L Microorganisms (U/mg of protein) Fermenter (U/ml of culture) E. coli 0.43 — ATCC35467/pCJ121 E. coli 4.95 30 ATCC35467/pCJ122 E. coli 0 — ATCC35467/pCJ123

TABLE 6 Fermentation Medium g/L Culture Condition glycerol 50 pH 7.0 (NH₄)₂SO₄ 6 Temperature of 33° C. KH₂PO₄ 2 800 rpm MgSO₄ · 7H₂O 1 1.0 vvm Yeast Extract 5 Trace Elements 1 ml Amino Acids (Threonine, Leucine, 0.5 Isoleucine, Valine, Histidine, Arginine)

6 1 4753 DNA Pseudomonas stutzeri CDS (1537)..(3603) 1 gatcgctggc gtactgcagg tagagcaggc gcatcggccc ccagggcgca tcggccggct 60 ccgctgtgcc ctgctggttc atgaagcgga cgaagcggcc atcgcggaac cgtggacgcc 120 attcggggct gtccgggtcg cggctgtcgg tgagcgtgcg ccacaggtcg ctgcgaaacg 180 gcggaccgct ccaaagcgcg ccgtggatgg gatcgccgag cagttcgtgc agctcccagg 240 aacgttgcga atgcagcgcg ccgaggctca ggccatgcag atacaggcgc ggtcggcgtt 300 cggccggcag ttcggtccag tagccataga tctcggcgaa tagcgcgcgg gccacgtcgc 360 ggccgtagtc ggcctccacc agcagcgcca gcgggctgtt cagataggag tactgcaacg 420 ccacgctggc gatatcgccg tggtgcaggt attccactgc gttcatcgcc gccgggtcga 480 tccagccggt accggtgggc gtcaccagca ccagcaccga tcgctcgaag gcgccgctgc 540 gctgcagctc gcgcaaggcc agacgcgccc gctggcgcgg ggtctctgcc gcgcgcagac 600 cgacgtagac gcgaatcggc tcgagcgccg agcggccgct caagacgctg atatccgccg 660 ccgacgggcc ggagccgatg aactcgcggc cggtgcggcc cagctcctcc cagcgcagca 720 acgaggcccg gctgccgctt ttcagcggcg aggccggtgg cgccgtctcc ggttcgatca 780 gggcgtcgta ctgcgcgaag gatgcgtcca gcatgcgcag tgcccgcgcc gccagcacat 840 cgctgagcag cgaccagaac agcgccagcg ccaccagcac gccgatcacg ttggccaggc 900 gccgtggcag cacgcggtcg gcgtgccgcg agacgaagcg cgacaccagc cgatacagac 960 gcgccagcgt cagcaggatg agaaaggtcg ccagcgcggt gagaatgact tcgagcaggt 1020 gcgcactgct caccggcggc atgcccatca gcgcgcgtac cgcgttctgc cagccggcga 1080 cctggctgag gaaatacccg gccagcagca ggcagccgac cgcgatcagc agattgaccc 1140 gctcgcgctg ccagcctggg cgctccggca gttccagata gcgccacagc cagcgccaga 1200 acacgccgag gccatagccc accgccagcg ccgcgccggc cagcacgccc tggctcagcg 1260 tcgagcgcgg cagcagcgat ggcgtcagcg ccgcgcagaa gaacagcgtg cccagcagca 1320 ggccgaaacc ggacagcgag cgccagatat agaggacggg caggtgcagc atgaagatct 1380 ccgcggtcgg gtgacggcgt cgcgcctcgg catatcgagg cgtgtccggt cgtgcggttc 1440 ccgtgatggt ccgcagcagg ccaatccgat gcaacgatgg ccgagcggcc gactcaaacg 1500 tctacatttc cctagtgctg ccggaaccga tcgccg atg agc atc cca gac aac 1554 Met Ser Ile Pro Asp Asn 1 5 acc tat atc gaa tgg ctg gtc agc cag tcc atg ctg cat gcg gcc cgc 1602 Thr Tyr Ile Glu Trp Leu Val Ser Gln Ser Met Leu His Ala Ala Arg 10 15 20 gag cgg tcg cgt cat tac gcc ggc cag gcg cgt ctc tgg cag cgg cct 1650 Glu Arg Ser Arg His Tyr Ala Gly Gln Ala Arg Leu Trp Gln Arg Pro 25 30 35 tat gcc cag gcc cgc ccg cgc gat gcc agc gcc atc gcc tcg gtg tgg 1698 Tyr Ala Gln Ala Arg Pro Arg Asp Ala Ser Ala Ile Ala Ser Val Trp 40 45 50 ttc acc gcc tat ccg gcg gcc atc atc acg ccg gaa ggc ggc acg gta 1746 Phe Thr Ala Tyr Pro Ala Ala Ile Ile Thr Pro Glu Gly Gly Thr Val 55 60 65 70 ctc gag gcc ctc ggc gac gac cgc ctc tgg agt gcg ctc tcc gaa ctc 1794 Leu Glu Ala Leu Gly Asp Asp Arg Leu Trp Ser Ala Leu Ser Glu Leu 75 80 85 ggc gtg cag ggc atc cac aac ggg ccg atg aag cgt tcc ggt ggc ctg 1842 Gly Val Gln Gly Ile His Asn Gly Pro Met Lys Arg Ser Gly Gly Leu 90 95 100 cgc gga cgc gag ttc acc ccg acc atc gac ggc aac ttc gac cgc atc 1890 Arg Gly Arg Glu Phe Thr Pro Thr Ile Asp Gly Asn Phe Asp Arg Ile 105 110 115 agc ttc gat atc gac ccg agc ctg ggg acc gag gag cag atg ctg cag 1938 Ser Phe Asp Ile Asp Pro Ser Leu Gly Thr Glu Glu Gln Met Leu Gln 120 125 130 ctc agc cgg gtg gcc gcg gcg cac aac gcc atc gtc atc gac gac atc 1986 Leu Ser Arg Val Ala Ala Ala His Asn Ala Ile Val Ile Asp Asp Ile 135 140 145 150 gtg ccg gca cac acc ggc aag ggt gcc gac ttc cgc ctc gcg gaa atg 2034 Val Pro Ala His Thr Gly Lys Gly Ala Asp Phe Arg Leu Ala Glu Met 155 160 165 gcc tat ggc gac tac ccc ggg ctg tac cac atg gtg gaa atc cgc gag 2082 Ala Tyr Gly Asp Tyr Pro Gly Leu Tyr His Met Val Glu Ile Arg Glu 170 175 180 gag gac tgg gag ctg ctg ccc gag gtg ccg gcc ggg cgt gat tcg gtc 2130 Glu Asp Trp Glu Leu Leu Pro Glu Val Pro Ala Gly Arg Asp Ser Val 185 190 195 aac ctg ctg ccg ccg gtg gtc gac cgg ctc aag gaa aag cac tac atc 2178 Asn Leu Leu Pro Pro Val Val Asp Arg Leu Lys Glu Lys His Tyr Ile 200 205 210 gtc ggc cag ctg cag cgg gtg atc ttc ttc gag ccg ggc atc aag gac 2226 Val Gly Gln Leu Gln Arg Val Ile Phe Phe Glu Pro Gly Ile Lys Asp 215 220 225 230 acc gac tgg agc gtc acc ggc gag gtc acc ggg gtc gac ggc aag gtg 2274 Thr Asp Trp Ser Val Thr Gly Glu Val Thr Gly Val Asp Gly Lys Val 235 240 245 cgt cgc tgg gtc tat ctg cac tac ttc aag gag ggc cag ccg tcg ctg 2322 Arg Arg Trp Val Tyr Leu His Tyr Phe Lys Glu Gly Gln Pro Ser Leu 250 255 260 aac tgg ctc gac ccg acc ttc gcc gcg cag cag ctg atc atc ggc gat 2370 Asn Trp Leu Asp Pro Thr Phe Ala Ala Gln Gln Leu Ile Ile Gly Asp 265 270 275 gcg ctg cac gcc atc gac gtc acc ggc gcc cgg gtg ctg cgc ctg gac 2418 Ala Leu His Ala Ile Asp Val Thr Gly Ala Arg Val Leu Arg Leu Asp 280 285 290 gcc aac ggc ttc ctc ggc gtg gaa cgg cgc gcc gag ggc acg gcc tgg 2466 Ala Asn Gly Phe Leu Gly Val Glu Arg Arg Ala Glu Gly Thr Ala Trp 295 300 305 310 tcg gag ggc cac ccg ctg tcc gtc acc ggc aac cag ctg ctc gcc ggg 2514 Ser Glu Gly His Pro Leu Ser Val Thr Gly Asn Gln Leu Leu Ala Gly 315 320 325 gcg atc cgc aag gcc ggc ggc ttc agc ttc cag gag ctg aac ctg acc 2562 Ala Ile Arg Lys Ala Gly Gly Phe Ser Phe Gln Glu Leu Asn Leu Thr 330 335 340 atc gat gac atc gcc gcc atg tcc cac ggc ggg gcc gat ctg tcc tac 2610 Ile Asp Asp Ile Ala Ala Met Ser His Gly Gly Ala Asp Leu Ser Tyr 345 350 355 gac ttc atc acc cgc ccg gcc tat cac cat gcg ttg ctc acc ggc gat 2658 Asp Phe Ile Thr Arg Pro Ala Tyr His His Ala Leu Leu Thr Gly Asp 360 365 370 acc gaa ttc ctg cgc atg atg ctg cgc gaa gtg cac gcc ttc ggc atc 2706 Thr Glu Phe Leu Arg Met Met Leu Arg Glu Val His Ala Phe Gly Ile 375 380 385 390 gac ccg gcg tca ctg atc cat gcg ctg cag aac cat gac gag ttc acc 2754 Asp Pro Ala Ser Leu Ile His Ala Leu Gln Asn His Asp Glu Phe Thr 395 400 405 ctg gag ctg gtg cac ttc tgg acg ctg cac gcc tac gac cat tac cac 2802 Leu Glu Leu Val His Phe Trp Thr Leu His Ala Tyr Asp His Tyr His 410 415 420 tac aag ggc cag acc ctg ccc ggc ggc cac ctg cgc gaa cat atc cgc 2850 Tyr Lys Gly Gln Thr Leu Pro Gly Gly His Leu Arg Glu His Ile Arg 425 430 435 gag gaa atg tac gag cgg ctg acc ggc gaa cac gcg ccg tac aac ctc 2898 Glu Glu Met Tyr Glu Arg Leu Thr Gly Glu His Ala Pro Tyr Asn Leu 440 445 450 aag ttc gtc acc aac ggg gtg tcc tgc acc acc gcc agc gtg atc gcc 2946 Lys Phe Val Thr Asn Gly Val Ser Cys Thr Thr Ala Ser Val Ile Ala 455 460 465 470 gcg gcg ctt aac atc cgt gat ctg gac gcc atc ggc ccg gcc gag gtg 2994 Ala Ala Leu Asn Ile Arg Asp Leu Asp Ala Ile Gly Pro Ala Glu Val 475 480 485 gag cag atc cag cgt ctg cat atc ctg ctg gtg atg ttc aat gcc atg 3042 Glu Gln Ile Gln Arg Leu His Ile Leu Leu Val Met Phe Asn Ala Met 490 495 500 cag ccc ggc gtg ttc gcc ctc tcc ggc tgg gat ctg gtc ggc gcc ctg 3090 Gln Pro Gly Val Phe Ala Leu Ser Gly Trp Asp Leu Val Gly Ala Leu 505 510 515 ccg ctg gcg ccc gag cag gtc gag cac ctg atg ggc gat ggc gat acc 3138 Pro Leu Ala Pro Glu Gln Val Glu His Leu Met Gly Asp Gly Asp Thr 520 525 530 cgc tgg atc aat cgc ggc ggc tat gac ctc gcc gat ctg gcg ccg gag 3186 Arg Trp Ile Asn Arg Gly Gly Tyr Asp Leu Ala Asp Leu Ala Pro Glu 535 540 545 550 gcg tcg gtc tcc gcc gaa ggc ctg ccc aag gcc cgc tcg ctg tac ggc 3234 Ala Ser Val Ser Ala Glu Gly Leu Pro Lys Ala Arg Ser Leu Tyr Gly 555 560 565 agc ctg gcc gag cag ctg cag cgg cca ggc tcc ttc gcc tgc cag ctc 3282 Ser Leu Ala Glu Gln Leu Gln Arg Pro Gly Ser Phe Ala Cys Gln Leu 570 575 580 aag cgc atc ctc agc gtg cgc cag gcc tac gac atc gct gcc agc aag 3330 Lys Arg Ile Leu Ser Val Arg Gln Ala Tyr Asp Ile Ala Ala Ser Lys 585 590 595 cag atc ctg att ccg gat gtg cag gcg ccg gga ctc ctg gtg atg gtc 3378 Gln Ile Leu Ile Pro Asp Val Gln Ala Pro Gly Leu Leu Val Met Val 600 605 610 cac gag ctg cct gcc ggc aag ggc gtg cag ctc acg gca ctg aac ttc 3426 His Glu Leu Pro Ala Gly Lys Gly Val Gln Leu Thr Ala Leu Asn Phe 615 620 625 630 agc gcc gag ccg gtc agc gag acc atc tgc ctg ccc ggc gtg gcg ccc 3474 Ser Ala Glu Pro Val Ser Glu Thr Ile Cys Leu Pro Gly Val Ala Pro 635 640 645 ggc ccg gtg gtg gac atc att cac gag agt gtg gag ggc gac ctc acc 3522 Gly Pro Val Val Asp Ile Ile His Glu Ser Val Glu Gly Asp Leu Thr 650 655 660 gac aac tgc gag ctg cag atc aac ctc gac ccg tac gag ggg ctt gcc 3570 Asp Asn Cys Glu Leu Gln Ile Asn Leu Asp Pro Tyr Glu Gly Leu Ala 665 670 675 ctg cgt gtg gtg agc gcc gcg ccg ccg gtg atc tgagcgccct cttcgcgcgc 3623 Leu Arg Val Val Ser Ala Ala Pro Pro Val Ile 680 685 cccgggtccg ccgctatagt gcgcagcgcc tggggcgcgc attgccctcg ccgtcgagac 3683 cagcccgtgt cgttcacttc gcttttccgc cttgcgctgc tgccgctggc gctgcttgcc 3743 gcacccgtct gggcgcagac cgcctgcccg cccggccagc agccgatctg cctgagcggc 3803 agctgcctct gcgtgccggc cgccgccagc gatccacagg cggtctacga ccgcgtccag 3863 cgtatggcta cgctggccct gcagaactgg atccagcagt cgcgcgaccg cctgatggcc 3923 ggcggcgtcg agccgatacc gctgcacatc cgctcgcagc tcgagccgta tttcgatctt 3983 gccgtgctgg agagtgcgcg gtaccgcgtc ggcgacgagg tggtgctgac tgccggcaac 4043 accctgctgc gcaacccgga cgtcaatgcc gtgaccctga tcgacgtcat cgtcttccgc 4103 cacgaggagg atgcccggga caacgtcgcg ctctgggccc atgagctcaa gcacgtcgag 4163 caatatctgg actggggcgt cgccgagttc gcccggcgct atacgcagga tttccgtgcc 4223 gtggagcgcc cggcctatgc gctggagcgt gaggtggaag aggccctgcg cgagacgcag 4283 acgcggcgct gagcgagctg atcggtgctg ctgcccgcac tgggctgaag cccaccaatg 4343 acgccggcga aaacgaaaaa ccccgccgag gcggggtttc tgacgcgggt tgtgcggtca 4403 gctcagaacg ccgggaccac ggcgcccttg tacttttcct cgatgaactg gcgtacttgc 4463 tcgctgtgca gcgcggcagc cagtttctgc atggcatcgc tgtccttgtt gtccggacgg 4523 gcgaccagaa tgttcacgta tggcgagtcg ctgccctcga tcaccagggc gtcctgggtc 4583 gggttcagct tggcttccag cgcgtagttg gtgttgatca gcgccaggtc gacctgggtc 4643 agcacgcgcg gcagagtcgc ggcttccagt tcgcggatct tgatcttctt cgggttctcg 4703 gcgatgtctt cggcgtggcg gtgatgccgg cgccgtcctt cagaccgatc 4753 2 689 PRT Pseudomonas stutzeri 2 Met Ser Ile Pro Asp Asn Thr Tyr Ile Glu Trp Leu Val Ser Gln Ser 1 5 10 15 Met Leu His Ala Ala Arg Glu Arg Ser Arg His Tyr Ala Gly Gln Ala 20 25 30 Arg Leu Trp Gln Arg Pro Tyr Ala Gln Ala Arg Pro Arg Asp Ala Ser 35 40 45 Ala Ile Ala Ser Val Trp Phe Thr Ala Tyr Pro Ala Ala Ile Ile Thr 50 55 60 Pro Glu Gly Gly Thr Val Leu Glu Ala Leu Gly Asp Asp Arg Leu Trp 65 70 75 80 Ser Ala Leu Ser Glu Leu Gly Val Gln Gly Ile His Asn Gly Pro Met 85 90 95 Lys Arg Ser Gly Gly Leu Arg Gly Arg Glu Phe Thr Pro Thr Ile Asp 100 105 110 Gly Asn Phe Asp Arg Ile Ser Phe Asp Ile Asp Pro Ser Leu Gly Thr 115 120 125 Glu Glu Gln Met Leu Gln Leu Ser Arg Val Ala Ala Ala His Asn Ala 130 135 140 Ile Val Ile Asp Asp Ile Val Pro Ala His Thr Gly Lys Gly Ala Asp 145 150 155 160 Phe Arg Leu Ala Glu Met Ala Tyr Gly Asp Tyr Pro Gly Leu Tyr His 165 170 175 Met Val Glu Ile Arg Glu Glu Asp Trp Glu Leu Leu Pro Glu Val Pro 180 185 190 Ala Gly Arg Asp Ser Val Asn Leu Leu Pro Pro Val Val Asp Arg Leu 195 200 205 Lys Glu Lys His Tyr Ile Val Gly Gln Leu Gln Arg Val Ile Phe Phe 210 215 220 Glu Pro Gly Ile Lys Asp Thr Asp Trp Ser Val Thr Gly Glu Val Thr 225 230 235 240 Gly Val Asp Gly Lys Val Arg Arg Trp Val Tyr Leu His Tyr Phe Lys 245 250 255 Glu Gly Gln Pro Ser Leu Asn Trp Leu Asp Pro Thr Phe Ala Ala Gln 260 265 270 Gln Leu Ile Ile Gly Asp Ala Leu His Ala Ile Asp Val Thr Gly Ala 275 280 285 Arg Val Leu Arg Leu Asp Ala Asn Gly Phe Leu Gly Val Glu Arg Arg 290 295 300 Ala Glu Gly Thr Ala Trp Ser Glu Gly His Pro Leu Ser Val Thr Gly 305 310 315 320 Asn Gln Leu Leu Ala Gly Ala Ile Arg Lys Ala Gly Gly Phe Ser Phe 325 330 335 Gln Glu Leu Asn Leu Thr Ile Asp Asp Ile Ala Ala Met Ser His Gly 340 345 350 Gly Ala Asp Leu Ser Tyr Asp Phe Ile Thr Arg Pro Ala Tyr His His 355 360 365 Ala Leu Leu Thr Gly Asp Thr Glu Phe Leu Arg Met Met Leu Arg Glu 370 375 380 Val His Ala Phe Gly Ile Asp Pro Ala Ser Leu Ile His Ala Leu Gln 385 390 395 400 Asn His Asp Glu Phe Thr Leu Glu Leu Val His Phe Trp Thr Leu His 405 410 415 Ala Tyr Asp His Tyr His Tyr Lys Gly Gln Thr Leu Pro Gly Gly His 420 425 430 Leu Arg Glu His Ile Arg Glu Glu Met Tyr Glu Arg Leu Thr Gly Glu 435 440 445 His Ala Pro Tyr Asn Leu Lys Phe Val Thr Asn Gly Val Ser Cys Thr 450 455 460 Thr Ala Ser Val Ile Ala Ala Ala Leu Asn Ile Arg Asp Leu Asp Ala 465 470 475 480 Ile Gly Pro Ala Glu Val Glu Gln Ile Gln Arg Leu His Ile Leu Leu 485 490 495 Val Met Phe Asn Ala Met Gln Pro Gly Val Phe Ala Leu Ser Gly Trp 500 505 510 Asp Leu Val Gly Ala Leu Pro Leu Ala Pro Glu Gln Val Glu His Leu 515 520 525 Met Gly Asp Gly Asp Thr Arg Trp Ile Asn Arg Gly Gly Tyr Asp Leu 530 535 540 Ala Asp Leu Ala Pro Glu Ala Ser Val Ser Ala Glu Gly Leu Pro Lys 545 550 555 560 Ala Arg Ser Leu Tyr Gly Ser Leu Ala Glu Gln Leu Gln Arg Pro Gly 565 570 575 Ser Phe Ala Cys Gln Leu Lys Arg Ile Leu Ser Val Arg Gln Ala Tyr 580 585 590 Asp Ile Ala Ala Ser Lys Gln Ile Leu Ile Pro Asp Val Gln Ala Pro 595 600 605 Gly Leu Leu Val Met Val His Glu Leu Pro Ala Gly Lys Gly Val Gln 610 615 620 Leu Thr Ala Leu Asn Phe Ser Ala Glu Pro Val Ser Glu Thr Ile Cys 625 630 635 640 Leu Pro Gly Val Ala Pro Gly Pro Val Val Asp Ile Ile His Glu Ser 645 650 655 Val Glu Gly Asp Leu Thr Asp Asn Cys Glu Leu Gln Ile Asn Leu Asp 660 665 670 Pro Tyr Glu Gly Leu Ala Leu Arg Val Val Ser Ala Ala Pro Pro Val 675 680 685 Ile 3 13 PRT Thermus aquaticus 3 Met Asp Pro Leu Trp Tyr Lys Asp Ala Val Ile Tyr Gln 1 5 10 4 18 PRT Pimelobacter sp. 4 Ser Thr Val Leu Gly Glu Glu Pro Glu Trp Phe Arg Thr Ala Val Phe 1 5 10 15 Tyr Glu 5 11 PRT Pseudomonas putida 5 Gly Lys Trp Pro Arg Pro Ala Ala Phe Ile Asp 1 5 10 6 12 PRT Escherichia coli 6 Ser Ile Pro Asp Asn Thr Tyr Ile Glu Trp Leu Val 1 5 10 

What is claimed is:
 1. An isolated trehalose synthase protein comprising the amino acid sequence as recited in SEQ ID NO:
 2. 2. An isolated trehalose synthase gene comprising the nucleotide sequence as recited in SEQ ID NO:
 1. 3. A recombinant plasmid containing the trehalose synthase gene of claim
 1. 4. The recombinant plasmid according to claim 1 which is recombinant plasmid pCJ122.
 5. A transformed E. coli with the recombinant plasmid of claim
 1. 6. The transformed E. coli according to claim 5 in which the recombinant plasmid is pCJ122.
 7. A process for producing trehalose which he trehalose synthase enzyme of claim 1 with obtain trehalose.
 8. A process for producing trehalose which comprises lysing the transformed E. coli of claim 5, centrifurgin lysed bacteria, and reacting the resulting supernatant with maltose solution to obtain trehalose.
 9. An isolated microorganism Pseudomonas stutzeri CJ38 produces trehalose from maltose. 